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\psplot[linecolor=blue]{-3}{3}{x 180 mul 3.1415 div sin}
\rput[l](3.1,0.1){$f$}
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\psplot[linecolor=green]{-3}{3}{x x 3 exp 6 div sub}
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\psplot[linecolor=orange]{-3}{3}{x x 3 exp 6 div sub x 5 exp 120 div add}
\rput[l](3.1,0.5){$p_{f,0}^5$}
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